According to who? These rumors float up every once and a while, but I've never seen a basis in fact. According to K. Ueshiba (who ought to know) his father had no interest at all in Chinese martial arts. He did spend some time in occupied Manchuria, but he did so at an exclusively Japanese institution. Further, if you're familiar with that time period in Japan you know that Chinese arts were virtually unknown here.

People's bodies all mover in the same ways. I'm not surprised to see similar approaches in different (and unrelated) arts, but that doesn't necessarily mean that there's a connection.